arrays.rb

# Ranges

range_1 = (1..10).to_a # includes the last element
p range_1

range_2 = (1...10).to_a # excludes the last element
p range_2

# Arrays

# index           0               1               2                   3
surfers = [ "Kelly Slater", "Mick Fanning", "John Florence", "Gabriel Medina"]
p surfers

# alternative syntax
# %w(Kelly\ Slater)

puts surfers.size
# Array#length / Array#count
puts surfers[1]

# surfers.push("Hugo Collado")
surfers << "Hugo Collado"
p surfers

# Reading
puts surfers[4]

# Updating
surfers[4] = "Hugo C. Centurion"
p surfers

# surfers.last or surfers[-1]


# insert at specific index
surfers.insert(2, "Julian Leopold")
p surfers


# Iterating over indexes with for

for index in (0...surfers.length)
  surfer = surfers[index]
  puts "#{index + 1} - #{surfer}"
end

# Iterating over elements
for surfer in surfers
  puts "Watching #{surfer}"
end

blocks.rb

def big_sort
  (0..1000000).sort
end

def timer
  start_time = Time.now

  big_sort
  yield # calls the block

  # once it's done executing the block
  # it resumes the timer execution

  end_time = Time.now

  end_time - start_time
end

time = timer do
  (0..1000000).sort
end

puts time

def greet(name)
  capitalized_name = name.capitalize

  # passes capitalized_name into the
  # block as an argument
  yield(capitalized_name)

  puts "[DEBUG] Block completed!"
end

greet("emma") do |capitalized_name|
  puts "Hello, #{capitalized_name}"
end

iterators.rb

surfers = [ "Kelly Slater", "Mick Fanning", "John Florence", "Gabriel Medina"]


surfers.each do |surfer|
  puts "Hello, #{surfer}!"
end

#            do                                 end
surfers.each { |surfer| puts "Hello, #{surfer}" }


# each_with_index : value, index
surfers.each_with_index do |surfer, index|
  puts "#{index + 1} - #{surfer}"
end

# map
upcased_surfers = surfers.map do |surfer|
  surfer.upcase
end

p surfers
p upcased_surfers

surfers_first_names = surfers.map do |surfer|
  first_name = surfer.split[0]
end

p surfers_first_names

# count will count element when return value is true
# return an integer
f_surfers_count = surfers.count do |surfer|
  last_name = surfer.split[1].downcase
  last_name.start_with?('f') # true
end
p f_surfers_count

# select => returns an array
surfers_with_last_name_f = surfers.select do |surfer|
  last_name = surfer.split[1].downcase
  last_name.start_with?('f') # true
end

p surfers_with_last_name_f

# find => returns the first element
# that evaluates to true
mistery_surfer = surfers.find do |surfer|
  last_name = surfer.split[1].downcase
  last_name.start_with?('f') # true
end

p mistery_surfer